Response of anopheles stephensi to deltamethrin in Lahore District, Pakistan

Abstract

In the present study, both males and females of Anopheles stephensi Liston were sampled from three different localities of Lahore district of Punjab, Pakistan. (Jaman, Mohlanwal and Noorpur Bhatta A1). Bioassays against 0.05 % deltamethrin were performed to evaluate the level of resistance in An. stephansi. All three populations were found susceptible to the WHO recommended dose of deltamethrin. Mortality rates were significantly higher in males than females. Biochemical tests were performed to measure the esterase activity, both in males and females of An. stephensi. All three populations displayed a large variation in the levels of both estrases A and B. Females were found to have significantly higher activity of esterase A and esterase B than males. Only one band (A1) was observed for esterase A in all three populations. For esterase B two bands (B1 and B3) were observed in Mohlanwal and Noorpur Bhatta A1. However, in Jaman a third bands (B2) of moderate intensity was also present between B1 and B3. Results of the present study suggested that present variations and high level of esterases in populations of An. stephensi in district Lahore are not associated with resistance against deltamethrin.